from the more-data-needed dept

I really haven't talked much (at all) about the "safety" concerns over the TSA's X-ray scanner devices, because a lot of it did seem like overreactions from people who didn't really know what they were talking about. However, there does appear to be increasingly credible claims from scientists that, at the very least, what the government is saying about these machines is not at all accurate. Keith Dawson points us to a blog post by Molecular Biologist Jason Bell, reviewing the literature on these devices and comparing it to questions sent by a group of scientists at UCSF, and suggesting (at best) that the government is being misleading in its claims about the safety of the devices. Here's just a snippet:

With respect to errors in the safety reports and/or misleading information about them, the statement that one scan is equivalent to 2-3 minutes of your flight is VERY misleading. Most cosmic radiation is composed of high energy particles that passes right through our body and the plane itself without being absorbed. The spectrum that is dangerous is known as ionizing radiation and most of that is absorbed by the hull of the airplane. So relating non-absorbing cosmic radiation to tissue absorbing man-made radiation is simply misleading and wrong. Of course these are related and there is over-lap, but we have to compare apples to apples.

Furthermore, when making this comparison, the TSA and FDA are calculating that the dose is absorbed throughout the body. According the simulations performed by NIST, the relative absorption of the radiation is ~20-35-fold higher in the skin, breast, testes and thymus than the brain, or 7-12-fold higher than bone marrow. So a total body dose is misleading, because there is differential absorption in some tissues. Of particular concern is radiation exposure to the testes, which could result in infertility or birth defects, and breasts for women who might carry a BRCA1 or BRCA2 mutation.

The report also notes that while the UCSF team was made up of well-known and well-respected scientists, the TSA's response included no author credits, and there's no indication that it was written by any actual doctors or scientists. I'm still not convinced the medical concerns are that big of a deal (well, perhaps for TSA agents stationed near the devices...), but it is a bit troubling that the TSA isn't being particularly forthcoming on this stuff.

Re: Re: Boycott Flying!

Ionising Radiation

With so much spoken about TSA Scanners, I have yet to read about the mA,kVP and duration of X-Ray exposure for each passenger, which will give a fairly good idea about the radiation - especially for frequent travelers and crew.

I am convinced that we don't know enough to justify it

There was a story out a year or two ago about CT scans done in emergency rooms. They apparently use a higher dose than normal x-rays but are more popular because they see more. The real problem highlighted by the story though, was that there was a wide range of levels of radiation being used by the machines, many times it was way more than needed to do the job. But there wasn't anybody monitoring the machines.

So if the medical community can't police their equipment, how is TSA going to be trusted to do it?

Re: I am convinced that we don't know enough to justify it

This is my main concern ... I assume that the machines were designed to limit the radiation levels to what is considered 'safe' but what if a machine malfunctions? They are being operated by the TSA not radiation experts, and there are hundreds, or maybe thousands, of them. I feel very confident that a machine will malfunction and produce dangerous levels of radiation, and that is not a risk that our government should be asking us to take, especially when the effectiveness of these machines is in question.

time differential

One aspect that I think has been glossed over when comparing radiation received from a scanning machine to that received during a flight is how long it takes to absorb that radiation.

A transcontinental flight takes several hours, during which you continuously absorb a little bit of radiation. The scanning process takes seconds, during which you receive (we're told) a similar amount of radiation. Think of it like sunbathing at the beach versus a quick trip to the tanning bed.

Not their decision

"I'm still not convinced the medical concerns are that big of a deal..."

Well, that's neither your decision nor their decision to make for me. Perhaps it's not big deal for an average individual, but what about those already predisposed to certain types of cancer? What about frequent fliers? What about those, as you mention, who spend day after day standing by these machines? In a hospital, radiologists stand behind shields to prevent the kind of exposure that TSA agents are subjected to daily.

The point is, these machines are potentially dangerous to some people, and it should not be the government's decision whether or not a person exposes themselves to that potential danger. A pregnant woman should not be compelled to act against her conscience and potentially threaten the welfare of her baby. Nor should she be punished by humiliating and painful groping for acting in her baby's best interest by refusing the scan.

Whether the concerns are overblown is not the issue. The issue is that there are legitimate medical concerns, no matter how minute, and there is no way that the government should have the power to compel an citizen to expose themselves to potential harm.

Re: Re: Not their decision

@Chronno:
Well, if you look at it from a risk:benefit ratio, since benefit has been effectively shown to be zero, no amount of risk would make this acceptable. =P

I think the safety is probably a nonissue, and is being overblown much like the benefits. I probably got hit with more radiation when I was working with a Co-60 irradiator. On the other hand, the less radiation the better, so it would still be wise to opt out if you have the time to spare. I mean, unless you like getting fried... oh wait, people do go to tanning beds.

Re: Re: Not their decision

Actually, whether the medical concerns are big or small is important to this argument. If the risk is small they can claim the gain outweighs the risk. If the risk is large, they can't.I recall someone doing the math using the TSAs radiation numbers on the increased risk of cancer due to a single dose of one of these scanners. They then compared it to the risk of being killed by terrorist action on any given aircraft flight. The numbers were approximately the same, so (if the math was right) effectivly the TSA, at optimistic estimate, is doubleing the chance of death from a single aircraft flight.

I am sad I cannot recall the source to double check the numbers, but if anyone else wanted to start over with the math I would be very interested.

what a huge suprise

Feel free to ignore but couldn't resist.....

troll

So the argument goes something like this?....

"Mr TSA, aren't these scanners unsafe?"
"Uh.. nope wrong.. safe and houses these things"
"Really?"
"No not really. Actually we don't have a clue whether they are or not, but then we don't give a monkeys either"
"Oh? Why's that?"
"Because it's all for the public safety and the 'Good of America'"
"Is it? How?"
"Uuuhhhh yes definitely - there's lots of proof"
"Oh good - where is it then?"
"Ummm well it's secret"
"There isn't really any is there?"
"Well you might think that but I couldn't possibly comment"
"So what's the real reason you don't care if they're safe?"
"Because someone somewhere is making a shed-load of cash out of....... uhhh I'd really rather not comment on that it's a matter of National Security"

Re: what a huge suprise

"Well you might think that but I couldn't possibly comment"

If that was an intentional quote from House of Cards then I salute you.

As for the actual story, I'm really struggling these days to believe anything someone in a position of authority tells me. I sometimes think that if at midnight a politician told me it was dark outside I'd probably still go and check.

Re: Re: what a huge suprise

I sometimes think that if at midnight a politician told me it was dark outside I'd probably still go and check.

Probably because, like me, you'd think that if they'd bothered to say that it's because they're busy setting up a large bank of floodlights around your house for "security" and just wanted to reassure you it won't really affect the "darkness" of your house at night at all.

Cumulative effects

One aspect of these devices that has been given short shrift in the media is the cumulative effects of this radiation. Each exposure increases your probability of getting radiation-induced mutations and damage to critical body systems. Frequent travelers are therefor much more susceptible to problems in the future as a result of this activity. Myself, I'll go for the pat-down and will complain as loudly as I can when I "get it in the shorts"... I'll also inform as many fellow travelers of the cumulative nature of this radiation as I can - maybe enough of them over time will decide that "hell no, we won't glow!"... :-(

Re:

This is something that I have wondered about. My mother is a nurse and used to have to wear one at the cardiologist office at which she worked despite not being a radiologist. If I were a TSA agent, I would be somewhat concerned about my exposure to stray radiation.

"I really haven't talked much (at all) about the "safety" concerns over the TSA's X-ray scanner devices, because a lot of it did seem like overreactions from people who didn't really know what they were talking about"

Re: Medical concerns

Millimeter wavelength is terahertz (THz) frequency while wifi is 2.4 GHz. So, yeah, close enough for government work.
Neither radio band is ionizing which means 'capable of knocking electrons out of atoms'. Radio doesn't do that; x-rays can.

Why not TLDs?

Back in the 80's when I was serving on a ballistic missile submarine, we all were required to wear a TLD at all times.

So why aren't the (presumably) well off and educated frequent fliers buying personal TLDs or other sorts of dosimeters and finding out what kind and level of zoomies they're getting?

In a quick google I see some personal units that run a AA batteries in the $500 range.

It's easily the fastest way to resolve the issue. If a handful of frequent fliers come forward with direct evidence that the cumulative dose they're getting is dangerous then the government can be told to sod off.

The TSA goons (sorry, they may not have created the TSA but if they're going to suck at that teat then they *are* its children) can pool their fast food lunch funds and buy one and take turns wearing it for a month at a time to see what's really happening to them.

Re: Why not TLDs?

"In a quick google I see some personal units that run a AA batteries in the $500 range."

I think you figured out why people aren't buying these things already. I won't pay $500 for a laptop, why would I pay that much for a one purpose device that the TSA would just shrug off as error prone (true or not, it's consumer grade not professional)?

Re: Re: Why not TLDs?

Several points:

Would you pay $500 for an x-ray at a hospital if it might detect a potentially life threatening problem? It's not just another "fun to have" consumer device, it's a diagnostic tool.

How many people do you know that fly frequently for months/years at a time that couldn't afford a $500 device? People that have to travel a lot are generally making pretty decent money and $500 is not an excessive expenditure. When I traveled frequently I blew better than $500 just on mini disc players and discs. Money is generally not an issue for the folks most at risk.

I didn't suggest that everyone buy one. It would only take a half dozen or dozen people showing concrete evidence that they had experienced unsafe levels of exposure from airport scanners to shut down the process.

The device isn't worthless after it has been used for 6 months or a year. I'm sure it has some resale value. Unlike a used laptop, I'd bet someone would snap one up on craigslist if it was listed at half retail.

$400 is about what my physician charges for very thorough annual physical exam, and two pair of decent eyeglasses run close to $600, so I don't see $500 as a ridiculous expense (though I acknowledge that medical insurance probably won't cover any of the cost of the monitor)

The average cable TV bill in the US is around $71/month. If the average family can afford $850 a year to watch reality TV and some football games then a one-time expense of $500 doesn't seem too insane, especially considering what it might prevent.

Re: Re: Re: Why not TLDs?

There is a slight flaw in your logic. Any long term tests on radiation exposure should have been done BEFORE the scanners were put into use. If they are so safe then as mentioned earlier someone should be able to tell us the exact mA/kVP and duration of the average scan.

All the safety issues aside, the TSA claims that these scanners are used on 1% - 2% of passengers that are randomly chosen. Maybe I'm just too stupid to understand national security, but how is the airplane safer if we are randomly superscreening a small percentage of people for no good reason? Wouldn't it be more effective to scan or grope EVERYONE?

Just to be clear, I think the whole thing violates the 4th Amendment, but Im just trying to make sense of the small percentage of random screening method.

Re: Why not TLDs?

Well if the TSA remains true to form, as soon as people started wearing a TLD or any other device that could accurately measure the amount of radiation exposure, all such devices would appear on the 'illegal to possess' list.

The TSA agent will remove any and all such devices before you get anywhere near the scanner, 'for security reasons'.

You can mail it back to yourself of let the friendly TSA agent dispose of it.

Or, under-reaction from know-it-all blogger.

Mike characteristically downplays any actual and substantial risks from gov't or corporations, while hyping trivia, same as the MSM does. He uses the Limbaugh technique of "I've looked into this and found nothing to worry about". In whatever degree, he too acts as authoritative gatekeeper of information, calming "overreaction", pooh-poohing fears, lulling you to sleep.

Here's game theory for you: if my "conspiracy theories" are wrong, then I lose nothing. But if you're wrong and there *is* an over-arching plan to implement a police state -- as if all the signs of it are just amazing co-incidence that lead in one direction -- then you and everyone you know lose their civil rights, probably forever.

When dealing with gov't, the least acquaintance with history should lead you to the view that gov't is always *evil*: "Gov't is not eloquence nor persuasion, but force; like fire, a dangerous servant and a fearful master." (Paraphrased.)

Anyhoo, plans are in motion to put the scanners into malls, courts, train and bus stations, so this uncontrolled experiment in causing cancer will likely get a really full scale test. If you're not "overreacting" now, it'll become routine.

Re:

If they were so casually dismissed, as you assert, then why both writing the article? Or would you rather not supply the statistics to sway Mike's opinion, since this is purely his opinion? So far the numbers that have been supplied haven't told us shit. Why? Because no one is supplying numbers!

Scare quotes

I really haven't talked much (at all) about the "safety" concerns over the TSA's X-ray scanner devices,

Why the quotes Mike? Are you suggesting that the concerns aren't really about safety? Or are you saying it's irrational to have concerns about the saftey of exposure to a type of radiation KNOWN to cause cancer? I get what you're saying about overreaction, but I don't get why you would belittle such concerns with the scare quotes.

Re: Why should we trust anything TSA says?

Fool me once, shame on me, fool me twice, shame on you,
Fool me three times, you must be government....

Wake up Sheeple, as long as you keep accepting the 'statements' being made, they will keep making them.

What happens if they lie (about looking at and taking pictures of some kid's 'junk') and get caught... Nothing
What happens if an individual lies and gets caught taking pictures of some kid's 'junk'... they get labeled a pedophile, put on the sexual offenders list for the rest of their life, and basically have their life ruined... seems fair, right?

Not that I'm in any way saying this shouldn't be the case, just that the 'punishment' should be the same in both situations. Personally I'd put em in stocks in the town square, with a nice sign and enough evidence to show what they did and let the town people sort things out (but I'd do the same to the TSA if given the chance)...